I thought it was 00 followed by the digits from the postal code. Many place just won't accept a CDN credit card at the pump.
This is one of the most irritating aspects of snowbirding. When DW and I are south we often go out for day long motorcycle rides. This might involve a fill to start the day then one or two as we put on miles.
That means standing in line 6 times every day we ride. What a PITA.
In Canada we have chip cards - enter PIN and you're done. Or tap and you're done. Or pump gas then go inside to pay you're done.